The perimeter of the rectangle is 68 mm. One side is 15% of the perimeter.

The perimeter of the rectangle is 68 mm. One side is 15% of the perimeter. What is the length of the second, not equal to the given side of the rectangle.

To solve this problem, remember that the perimeter of a rectangle is the sum of the lengths of all its sides. Since in a rectangle the opposite sides are equal, then P = 2 * (a + b), where a is the length, b is the width. Knowing that one side is 15% of the perimeter, that is, from 68 mm, we calculate its length. To find the percentage of the number, you need to multiply this number by the percentage and divide by one hundred.
a = 68 * 15/100 = 68 * 0.15 = 10.2 cm.
Let’s calculate the length of the second side.
2 * (10.2 + a) = 68;
10.2 + a = 68/2;
10.2 + a = 34;
a = 34 – 10.2;
a = 23.8;
Answer: 23.8 cm.